The current state of the art for coping with snow and ice on roads usually involves applying a deicer material such as a salt to the road surface. Sometimes antiskid materials such as sand or other aggregates such as gravel are added with or without a salt.
The use of salt and compositions having high concentrations of salt, cause an undesirable corrosive effect on vehicles, the road surface, and the environment with respect to the run off of water containing salt which contaminates the surrounding land and water.
Considering the above problems associated with salt formulations, there has been a continuing need for a deicing composition or formulation which can effectively melt snow and ice yet which reduces the corrosion and environmental contamination referred to above. In response to the above problems associated with the use of road salt, the prior art has looked to alternative formulations which are less corrosive and more environmentally friendly.
U.S. Pat. No. 5,922,240 (Johnson et al.) relates to a deicing composition comprising brewers' condensed solubles produced, for example, as by-products from a commercial beer brewing process, which by-products are biodegradable. The invention also relates to the use of a deicing composition to reduce the buildup of snow and ice on road, bridges and other outdoor surfaces.
U.S. Pat. No. 5,635,101 (Janke et al.) relates to a deicing composition containing a by-product of a wet milling process of shelled corn. Corn kernels are steeped or soaked in a hot solution containing small amounts of sulfurous acid. The corn kernels are separated from the steep water and steep water solubles are used in the production of a deicing composition.
U.S. Pat. No. 4,676,918 (Toth et al.) relates to a deicing composition which comprises a mixture containing at least one component selected from a number of chlorides or urea and an admixture of waste concentrate of alcohol distilling that has a dry substance content of from 200 to 750 g/kg and from 10% to 80% by weight of water.
The materials described in the above three patents are naturally occurring substances with hundreds (if not thousands) of components such as complex carbohydrates, starches, sugars, proteins etc. and are normally used with a salt.
The above described de-icing solutions which employ agricultural residues e.g., corn based distillers soluble and soluble from the corn wet milling industries, brewers condensed soluble, and distillers condensed soluble are extremely variable in composition, viscosity, film forming tendency, freezing temperature, pH etc., and consequently give varying performance when used in de-icing solutions. Depending upon the source and batch, these materials at low temperatures sometimes exhibit such resistance to flow that they cannot be applied evenly to a road surface or mixed with a chloride, rendering them virtually unsuitable for use.
Furthermore, these patents utilize materials which have highly undesirable or unnecessary ingredients leading to practical difficulties by manufacturers and users, such as stratification in storage, biological degradation, odor, plugging of filters and spray nozzles and environmental difficulties e.g. high biological oxygen demand due to the very high organic contents (about 40% by weight), and the presence of phosphorus compounds, cyanide and heavy metals.
To improve quality and performance, and to meet current mandated standards, there has been a continuing need for a source of carefully controlled residuals and by-products which exhibit improved performance and reduce metal corrosion, spilling of concrete, toxicity and address environmental concerns.